The Ars visitors came from Apple; staffers were able to match the device IP address with Apple's corporate IP block. While it is very unlikely that iOS 6 will be announced simultaneously with the new iPad on Wednesday, it appears that Apple is beginning to test early versions of the next mobile OS in-house.

The screenshot (shown above) also show that the iOS 6 devices are running a slightly newer version of WebKit, the layout engine that powers the Safari web browser. Devices running iOS 5.0.1 display a WebKit version number of 534.46, while the iOS 6 devices are displaying 535.8.

We're in agreement with Ars on one point -- iOS 5.1 will most likely be introduced on Wednesday at the Apple event or shortly thereafter, while iOS 6 will arrive in the late summer or early fall on a next-generation iPhone.